JPS62104432A - Booster source - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a booster power supply device for supplying a voltage to a load after compensating it with a voltage-to-booster converter of a DC power supply having voltage fluctuation factors such as a storage battery. The present invention relates to an overcurrent protection method for a booster converter.

[Conventional technology]

The following method is known as a method for supplying a voltage within a specified range from a storage battery power supply having a voltage fluctuation factor to a load during a power outage.

C) An end battery system in which the number of cells connected in a storage battery is increased by sequentially switching them with an arsenal contactor as the output voltage drops.

1) An SID method that reduces the voltage drop by short-circuiting a silicon dropper magnetic contactor inserted between the storage battery and the load.

(c) Voltage compensation DC/DCC/equation converter (referred to as J-1 lower Fustar converter) Z configuration is a booster power supply system in which this output voltage is superimposed on the DC input voltage.

The present invention relates to the above-mentioned booster@mud method.

Conventional Booster Denryoman Type Z Referring to FIG. 4, a DC power source (2) having a voltage fluctuation factor is connected to a commercial AC power source (1). This DC power source (2) consists of a rectifier circuit and a bank-up storage battery charged by the rectifier circuit, and is connected to a load 14'r through a booster converter device (3) with seven valves. The booster converter device (3) compensates for boosting the DC power supply voltage Vi, which has fluctuation factors, using the output voltage V, and supplies a voltage vLZ within a specified range to the load (4). In the example of FIG. 4, the booster converter device (3) is a first booster converter group (3A ) and a second booster converter group (3B) consisting of two booster converter devices (3B, ) (3B2).

Each group (3A) (3BJ booster converter unit (3A, J~(3A4), (3B+J and (3B2))
The DC input terminals of are respectively connected to the DC power source (2), and the DC output terminals are connected in parallel to each other and connected between the lower end of the DC power source (2) and the lower end of the load (4).

(5) is a current detector, which detects the total current flowing through the load (4) by connecting two booster converter groups (3A
) (3B) is connected to the output line. (6) is an overcurrent detection circuit, which detects an overcurrent state based on the output of the current detector (5). Note that the overcurrent detection level of this overcurrent detection circuit (6) is set to a level that can protect the booster converter and converter (3) 7 from overcurrent. (7) is a switch consisting of an electromagnetic contactor, which is connected between the output terminals of the booster converter group +3A) and [3B), and becomes closed in response to the overcurrent detection signal of the overcurrent detection circuit (6); Booster converter group (3
A) Cut off the current flowing through C3B) to protect it.

[Problem that the invention seeks to solve]

However, this conventional booster converter device has the following drawbacks. After the equipment is installed, if it becomes necessary to add a booster converter unit Z due to an increase in the load, the design will be revised and a current detector, overcurrent detection circuit, and switch with a large capacity commensurate with the addition will be installed. They had to be replaced and it was difficult to add more. If expansion is expected in the future, it is necessary to use a large capacity current detector, overcurrent detection circuit, and switch in advance in anticipation of the capacity after expansion, and the initial cost is considerably high. In addition, there is another problem in that the overcurrent setting level of the overcurrent detection circuit must be reset.

[Means to resolve the request for assistance]

In order to solve the above problems, in the booster power supply device of the present invention, a plurality of booster converter units are divided into a plurality of groups, and each group is provided with a current detector, an overcurrent detection circuit, and a switch. Furthermore, each group is provided with a load current bypass diode. Further, a circuit is also provided for controlling all of the booster converter units to stop when at least one of the booster converter units is in an overcurrent state. The overcurrent detection levels of each group are set substantially equal to each other, and the current capacities of the bypass diodes of each group are set to be equal to each other. What is the level at which overcurrent of the booster converter unit is detected for the above stop control?

The setting is such that the booster converter unit is controlled to stop before the switch becomes closed, allowing current to flow through the bypass diode.

[For production]

In the booster power supply device of the above invention, when an overload state (overcurrent state) occurs, each booster converter unit is controlled to stop by the stop control circuit.As a result,
The bypass diode, which has been reverse-biased by the output of the booster converter and has been in an off state, is now turned on, and the load current flows through it. This is because the current capacity of the bypass diodes in each group is set approximately equal.

The load current is divided approximately equally between each group. When an overcurrent is detected by the group overcurrent detection circuit, the switches (for example, electric contactors) of each group are turned on.

The load current flowing through the bypass diode is transferred to the switch, which has lower resistance than the diode. What is important here is that the current capacity of the bypass diodes in each group is set to be the same, so if the number of booster converter units included in each group is the same, the booster converter units will not be controlled to stop. This means that approximately the same load current flows through each group. Therefore, it is possible to set the detection levels 7 of the current detectors and overcurrent detection circuits of each group to the same level, and even if they are set the same level, no hunting operation occurs. Therefore, even if a booster converter unit is added to a group with a small number of booster converter units, it is not necessary to replace the current detector of the group or change the setting of the overcurrent detection level.

〔Example〕

Next, a booster power supply device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3. However, the code 1 in Figure 1
Components 11 to (4) are substantially the same as those designated by the same reference numerals in FIG. 4, so their explanation will be omitted.

This booster power supply device includes first and second booster converter groups (first and second group current detectors +5a corresponding to 3AJ (3B)) [5bJ, first and second group overcurrent detection circuits] (6a) (6J, switch (7a) (7b) consisting of first and second electric contactors, first and second bypass diodes DI''-D, , D, ~D4, Furthermore, it has an OR gate circuit (81) and a stop control circuit (9).

The first and second group current detectors (5a) (5b,) are connected to the current paths of the first and second booster converter groups.
and detects the load current of each group. These group current detectors (5a) (5b) have almost the same current capacity each other despite the difference in the number of booster converter units in one group.First and second group overcurrent detection Circuit (6a
, ++6b) responds to the output of each group current detector (5aJ (51)) and detects whether this output is equal to or higher than the group overcurrent detection level, and is set to the same group overcurrent detection level. has been done.

The first and second switches +7a) (7b) have the same current capacity and each booster converter group (3A) (3B
) is connected between the pair of output lines, and responds to both outputs of the first and second group overcurrent detection circuits (6a) and (6b).

The first bypass diodes D, ~D4 are two booster converter units) +3AI) ~ (3A4) K
(4 booster converter units are provided for each booster converter unit)
(3A,] to (3A, J) are connected between the output lines. 4 in the second booster converter group [3B]
2 of the second bypass diodes D;~D4'
The booster diodes D, D2 are already installed in the booster converter unit) (381) +382
), and the remaining two booster diodes D, , D, are connected between the lines to be added. 8 bypass diodes D.

~D4. Since DI~D are diodes of substantially the same structure with almost the same current capacity 7, the total current capacity of the four first bypass diodes D,~D4 connected in parallel with each other and the diodes in parallel with each other The total current capacity of the four connected second bypass diodes D, ~D is approximately equal. Note that the total current capacity of each of the first and second bypass diodes D1 to D4, D, and D4 is as follows:
This is above the overcurrent detection level side of the first and second overcurrent detection circuits +6a) and (6b).

! Figure 2 shows the booster converter unit (3A,
) and stop control circuit are specifically shown. In addition, other booster converter units) (3A2) to (38).

), (3B,) (3B2) are constructed exactly the same as the booster converter unit) (3A,) shown in FIG. In Figure 2, the booster converter unit) (
3A, ) is the primary winding U of the output transformer (10), one end of which is connected to one end of the DC power supply (2) in FIG.
A switching element (121) consisting of a transistor connected between the other end of this primary winding Uυ and the other end of the DC T source (2) in FIG. 1, and the secondary winding 03 of the transformer (10) It is equipped with a rectifier flat shoulder path I connected to a switch element α power control circuit 05), a current detector (16), and first and second overcurrent detection circuits aηα8).

To explain each part in more detail, the output rectifier half-frame circuit tta
It consists of a rectifier diode α9, a half-screen diode 4, a half-screen actuator, and a half-screen capacitor, and the output voltage is V. , output current engineer. The current detector (IU consists of a current transformer (CTI) connected in series with a transistor as a switching element q, the primary winding of the output transformer (10) (Ill and the switching element 0.21 The output of this current detector (Ifil) corresponds to the output current T of the booster converter unit (3A).

The first overcurrent detection circuit consists of a comparator (23) and a first reference voltage source. The inverting input terminal of the comparator (23) is connected to the current detector [161], and the non-inverting input terminal is connected to the reference voltage source C1!4), so that the voltage is given from the first reference voltage source C4). The first reference voltage I corresponding to the first overcurrent detection level]
When the output of llit becomes thick, the comparator (23) sends out a low level output Z indicating an overcurrent.

The second overcurrent detection level consists of a comparator (2) and a second reference voltage source 06+.The non-inverting input terminal of the comparator (251 is connected to the current detector (161), and the 2 of the reference voltage (2[i+), the output of the current detector σIj is lower than the second reference voltage V2 corresponding to the second overcurrent detection level given from the second reference voltage source Q61. When becomes large, the comparator (251) sends out a high level output indicating overcurrent 7.

The control circuit 05) includes a voltage control error amplifier 12, a reference voltage source Qa, a comparator, and a triangular wave generator #30).

Drive circuit QJ1 and three LD'X-E A--D C3D
C32] (33+).The non-inverting input terminal of the error amplifier port is connected to the load (
4) The 1 inverting input terminal connected to one end is the reference voltage source Q8.
Because it is connected to 1.

The output corresponding to the difference between both inputs is input to the inverting input terminal of the comparator (29. The comparator is a triangular wave generator ■) that is supplied to the non-inverting input terminal, and the error is supplied to the inverting input terminal. Compare the output with the error output, J:! II also generates a high level output pulse corresponding to a period in which the triangular wave voltage is high. This high level output pulse or diode 3]J
and a drive circuit (35) to the base of the transistor as the switch dyad σ2, and the switch element σ2
is controlled on. Therefore.

The on/off period of the switch element (121) matches the period of the 3' PJ wave. When there is no overcurrent state, the diode r33 is kept off, and the first and second overcurrent detection circuits aη( 181 is a switch element (unrelated to on/off control of 12);

The output line of the first overcurrent detection circuit (1η) is connected to the output line of the comparator (29) through a diode (3:yv valve). The output line of the second overcurrent detection circuit 08 is The gate circuit (8) is connected to the input terminal of the stop control circuit (9) through the χ valve.The stop control circuit (9) is connected to the booster converter unit +3A+) to (3B2) (
7) This is a circuit that stops the operation '1', and the comparator Q in the previous stage
9, the output current is lower than the second overcurrent detection level. It consists of a monostable multivibrator that is triggered by an output indicating that the signal has become large and sends out a low-level stop control signal for a fixed period of time (for example, a few seconds). Note that this stop control circuit (9) does not have a timer configuration consisting of a monostable multi-by-break, but is configured with a flip 70 tube, for example, and is set by the overcurrent detection signal of the second overcurrent detection circuit (8). As a result, the stop control signal may be outputted, and then the stop control circuit may be terminated by being reset. The stop control circuit (9) includes an OR gate circuit (8) with 7 valves, and all booster converter units (3Al) to (3Al) shown in Figure 1 are connected to the stop control circuit (9).
B2) C1 The output of the second overcurrent detection circuit is input. Also.

The output of this stop control circuit (9) is the output of all booster converter units +3AIJ~(3A4), (3B+
) (3B2). Therefore, if any one booster converter unit becomes overcurrent, all booster converter units +3A, 3~(38
2,) stops.

Next, the operation at the time of overcurrent will be explained. Now, if the load current TL is less than the first current value shown in FIG. 3, then the power supply voltage V1 and the booster converter output voltage V. applied approximately constant output voltage Vi + V.

is obtained. That is, a specified load voltage V that is boost-compensated is obtained. On the other hand, the load current TL is null at the overcurrent level D1! : , Faster converter unit (3A1)
~[3A4,1, (3Ph) (3B2) respective output currents. becomes equal to or higher than the first overcurrent detection level in the first overcurrent detection circuit (Lη), and the output of the first overcurrent detection circuit aη becomes a low level. As a result, the diode (331 becomes conductive, and the control The output line of the comparator for pulse formation is the diode (33) and the comparator I23I.
The control pulse goes into a low level state, and the control pulse @ is limited.

Therefore, the on-period of the switch element (121) becomes shorter, and the output voltage V drops as shown in FIG. , the output voltage V does not become zero due to the accumulation time of the switch element (121) and the operation delay of the control circuit, and the bypass diodes D1 to D, , D
, ~D4's reverse bias is maintained. For this reason.

Booster converter unit (3A,) ~ [3A,)
, (3BI) (3BI) (If the load current continues to flow through 3BZJ and the load current increases, the output current ■. also increases. When the load current TL reaches T2 shown in FIG. 3, the output current T of the booster converter unit. The booster converter unit +3A, J ~ (3A,) has also increased accordingly.
, (3B, J (Part or all of the output current T of 382J becomes higher than the second overcurrent detection level, and the comparator (
The output of 251 switches to high level and the stop control circuit (9)
is triggered.

A low-level stop control signal is output from here. Therefore,
Even if a high level control pulse is generated from the comparator, it flows into the stop control circuit (9) via the diode GzZ and is not supplied to the switch element σ. As a result, during the period when the stop control circuit (9) is in the low level state.

All booster converter units (3A, ) to (3A
,).

(3BI) (3B2) becomes stopped. As a result, the booth, converter unit) (3Al) ~ (3B
2) Output voltage V. becomes zero, and the reverse bias of the bypass diodes D, ~D4゜D, ~D4 is released,
These become conductive. Bypass diode D, ~
D4, D+ to D; have the same electrical characteristics, so the total current of the four bypass diodes D1 to D4 of the first booster converter group (3A) and the current of the second booster converter group (The total current flowing through the four bypass diodes D1 to D4 of 3BJ is almost the same. That is, the total current flowing through the four bypass diodes D1 to D4 is almost the same.
,, D; ~ Before D4 becomes conductive, the current in the first booster converter group (3A) flows into the second booster converter group (3A).
Although the current is twice that of 3BJ, the bypass diode D
After 1~D, ,D,~D4 are made conductive, they become equal to each other.

When the load current ■ increases further to 13 in Figure 3.

A signal indicating that either one or both of the group overcurrent detection circuits +6a) and (6b) exceeds the group overcurrent detection level is sent out, and the switch (7a)
+7b) becomes closed at the same time. As a result, the current that has been flowing through the bypass diodes D1-D, , D, '-D; is now transferred to the switches (7a) [7b] with low resistance. Since the switches (7al and 7b) have almost the same internal resistance, they share 1/2 of the load current.Switching 1
5c7a)C7b) are closed, booster converter units (3A,) to (3A,), (3B+) (3
B2J and of course bypass diodes D1 to D4
．． Since no current flows through D,' to D4', these are protected from overcurrent.

By the way, if the bypass diodes D1 to D, , I); to D'4 according to the present invention were removed from the circuit of FIG.

In addition, in anticipation of expansion, the first and second overcurrent detection circuits (6
If the overcurrent detection levels of aH6bJ are set to the same level, a hunting state will occur. To explain this in detail, it is the booster converter unit 3A.

~3A313. and 3132 are in operation, the second booster converter group (3AJ receives twice the current of the second booster converter group (3BJ), so in an overcurrent state, the first] overcurrent detection circuit (6a) An overcurrent is detected and the first and second switches (7aH7bJ are closed. As a result, the first and second switches (73H7bJ) are closed.
t)) shares the load current by 1/2, the current of the first switch (7aJ) and current detector (5a) decreases,
The transmission of the overcurrent detection signal from the overcurrent detection circuit (6a) stops, and the switches +7a) and (7b) become open. Therefore, again booster converter units 3A, ~3
Load current flows through A, 3B, and 3132.

If the overcurrent condition has not been resolved, the overcurrent detection signal is generated again and the switches +7a) (7b) are closed. In other words, repeated opening and closing operations () and nching operations of the switch (7aN7J) occur.In addition, such non-nching operations occur in the booster converter unit (3A,
)~T3A, ), (3B,) and (3B,), the bypass mode D,~D D: and D
This also occurs when only : is provided and D' and pan are not provided. On the other hand, in the circuit of FIG. 1 according to the present invention, the first
and second booster converter group (3A) (3B) K bypass diodes D1 to D4, D with the same current capacity
Since r to D4 are connected, the current sharing becomes equal.

Hunting action does not occur.

In the circuit shown in Fig. 1, when booster converter unit (31) is not boosting the voltage, booster converter units (3A,) to (3A,), (3B,) and (3B2) are stopped and bypassed. Diode D1
Load current is supplied through the valve ~D; ~D:. When an overcurrent condition occurs from this state, the switch (7
aJ (7bJ is closed and bypass diodes D1 to D4
, D, ~D4 are protected. Note that one figure is not shown.

Indicates an overcurrent condition when switch 17a)C7b) is closed.
A circuit is provided to generate an alarm.

When load demand increases and expansion becomes necessary.

A booster converter unit is added to the second booster converter group (3B). At this time, the current detector (5b)
, overcurrent detector C6b), switch [7b], etc., or setting changes are not required. In Fig. 1, it is possible to add two booster converter units to the chassis.

If you want to add more, add a third booster converter group, a third current detector, a third overcurrent detection circuit, and a third
It is sufficient to install a switch.

[Modified example] The invention is not limited to the embodiments described above.

It is a strange, formable thing. For example, the four bypass diodes D, ~D, ,D, ~D4 of the first and second groups can each be replaced with one diode. Further, the stop control by the stop control circuit (9) may be performed on the input side of the comparator f291 in FIG. 2. Alternatively, a current detector may be connected to the output line of the booster converter unit, and the output current T0 detected by the current detector may be inputted to the second overcurrent detector 1tus+ for stop control. Also, in FIG.

First and second booster converter groups + aA) (3B
) Place three booster converter units each.

It is also possible to add one unit to each group.

〔Effect of the invention〕

As is clear from the above, according to the present invention, even if there is a difference in the stand R of the booster converter unit between a plurality of groups,
The current capacity of the bypass diodes is set to be the same in advance, and the switch is closed after current flows through the bypass diode, so even if a booster converter unit is added, the booster converter There is no need to redesign or adjust overcurrent detection circuits and switches for each group. It was a cabinet. When adding a new booster converter group, it is sufficient to simply connect the same ones as the existing group in parallel. Therefore.

The addition of converter units can be achieved extremely easily and economically.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a booster power supply device according to an embodiment of the present invention. FIG. 2 is a circuit diagram showing a part of FIG. 1 in detail. FIG. 3 is a characteristic diagram showing the relationship between load current and load voltage of the device shown in FIG. 1. FIG. 4 is a block diagram showing a conventional booster power supply device. (1)...Commercial AC power supply, (2)...DC power supply, (
3)...Booster converter device, (3A)+3B
)...first and second booster funverme groups, (
3A+) ~ +3A4) (381) (3B2)...
Booster converter unit, (5aJ (5b)...
Current detector, T6a) f6b... overcurrent detection circuit,
(7aJ (7b)...Switch, Dr~D, ,
D, ~D4... Bypass diode. (4) Load.

Claims (1)

[Claims] (1) A booster power supply device in which a plurality of booster converter groups each consisting of a plurality of booster converter units connected in parallel are connected between a DC power source and a load, and each of the booster converter groups is connected in parallel to each other, a group current detector for detecting a current flowing through the booster converter group; a group overcurrent detection circuit for detecting an overcurrent in the booster converter group based on an output of the group current detector; and a group overcurrent detection circuit for bypassing the load current. A bypass diode for short-circuiting the bypass diode and a switch for selectively short-circuiting the bypass diode are respectively provided corresponding to each of the booster converter groups, and the overcurrent detection levels of the overcurrent detection circuits for each group are approximately equal to each other. The current capacities of the bypass diodes are set equal to each other, and the current capacities of the bypass diodes are set equal to or higher than the load current value corresponding to the overcurrent detection level of the group overcurrent detection circuit, and are set to be substantially equal to each other, and the bypass diodes are set to be equal to each other, are connected between the output lines of the converter group, each of the switches is connected in parallel to each of the bypass diodes, and becomes closed in response to any overcurrent detection signal of each of the overcurrent detection circuits. a booster converter unit overcurrent detection circuit is provided in at least one of the booster converter units, and the booster converter unit overcurrent detection circuit responds to a signal indicating overcurrent detection generated from the booster converter unit overcurrent detection circuit; and a circuit for stopping and controlling all the booster converter units in each booster converter group, and the overcurrent detection level of the booster converter unit overcurrent detection circuit is controlled based on the overcurrent detection by the group overcurrent detection circuit. A booster power supply device characterized in that the value is set to such a value that the stop control signal can be generated from the stop control circuit before the switch is brought into the closed state.